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UNITED STATES PATENT O FICE.

JEAN J. D. HUTINET AND PIERRE E. LAMY, or PARIS, FRANCE.

PREPARATION OF PHOTOGRAPHIC PAPER FOR MAKING GELATINE BROMIDE 0F S ILVER PRINTS.

SPEGIFIOATION forming part of Letters Patent No. 253,827, dated February 14, 1882.

Application filedAprilQl, 1881. (No specimens.) Patented in France April5,1881.

To all whom it may concern.-

Be' it known that we, JEAN JOSEPH DEsIEE HUTINET and PIERRE ERNEST LAMY, both of Paris, in theRepublic ofFrance,have invented a new and useful Improvementin the Preparationof Photographic Paper for Making Gelatine Bromide of Silver Prints, of which improvement the following specification is a full description.

This invention relates to the preparation of paper'with gelatine or other gummy or albuminous matter which is insoluble or is rendered insoluble in cold water and with bromide of silver or other silver precipitate insoluble in water, and has for its. object so to prepare the paper that brilliant prints or positive proofs are at once obtained. The plan heretofore adopted has been to apply directly upon the paper a sensitive layer composed of gelatine and a 'chloride, iodide, or bromide of silver, or other insoluble silver precipitate or mixture of such precipitates, and, afterexposin g the paper thus prepared under a negative to natural or artificial light to develop the image, with alkali, with oxalate of iron, orwith pyrogallic acid. Such prints are, however, pale, dull, and disagreeable, and to render them acceptable it is necessary, after development, to cover them with encaustic albumen, collodion, or varnish. This last operation adds greatly to the labor, and interferes with the general employment and consequently with the manufacture and sale of the paper prepared with gelatine and the bromide or similar compound of silver.

With'paper prepared in accordance with this invention images as brilliant as, or, if desired, more brilliant than, those produced by chloride of silver with paper once or twice albumenized are obtainedafter exposure and development at once and without further treatment.

' The invention consists in applying as well the varnish or composition for imparting brilliancy as the gelatine-bromide compound in the preparation of the paper, so that the pellicle containing the gelatine-bromide compound is Itself rendered brilliant. The paper may be calendered or not, as deemed necessary or desirable.

The following are illustrations of a number of ways in which the invention is or may be carried into efiect.

First method.The paper is covered with a and bromide or other suitable compound of silver in any ordinary or suitable way. The bromide is preferred over other silver-compounds on account of its great sensitiveness.

Second 'mcthod.The paper is covered with' a solution of resin or gum-resin in alcohol, an essence, an alkaline or saline solution, or other suitable solvent. After drying it is calendered,

and it is'then covered with the sensitive layer of gelatine-bromide of silver.

Third method-The paper is covered with a varnish of collodion, and is then, with or without calendering, coated with the sensitivelayer of gelatine-bromide of silver.

Fourth method.Tl1e paper is coated with the sensitive layer of gelatine and bromide of silver, and then, after drying and before printing, is covered by means of a brush, a bath, or a mechanical roller with the solution of awhite resin or gum-resin in alcohol, essence, alkaline or saline solution, or other solvent. Prepared in this way the layer for imparting brilliancy to the print is hard and insoluble.

Fifth method.--The solution of resin or gumresin is mixed with the sensitizing composition of gelatine and bromide of silver, and the paper is covered with the mixture.

Sixth method-The paper is prepared as in the fifth method, and after drying is coated with the solution of resin or gum-resin by itis prepared, the development of the image after exposure under the negative is or may be made in the ordinary way, either by the upper surface, on which the layer or layersare applied, by the under surface, or by both surfaces simul taneously. After this development and after washing, treating with a gold solution or obtained which is brilliant, very brilliant, or

extra brilliant, according to the method em-.

ployed and the proportion of resin incorporated in the solution used.

Having now fully explained our invention and themanner of carrying the sameinto effect, what we claim isl. The method of preparing photographic paper with gelatine-bromide of silver or analogous sensitive compound for positive printing, which consists in applying, in connection with said compound, a varnish for imparting brilliancy, and thus rendering brilliantthe sensitive pellicle itself, so that varnishing after the priutingoperation is rendered unnecessary, substantially as described.

2. Photographic paper prepared for positive printing with a sensitive pellicle of gelatine- 2c bromide of silver or analogous compound, combined with a varnish for imparting brilliancy, substantially as described.

3. Photographic paper prepared forpositive printing with a sensitive pellicle of gelatine- 2 bromideof silver or analogous compound, combined with avarnish for imparting brillianey, and caleudered, substantially as described.

In witness whereof we have hereunto signed our names in the presence of two subscribing 30 witnesses.

JEAN JOSEPH DESIRE HUTINET. PIERRE ERNEST LAMY.

Witnesses:

Itonr. M. HOOPER, *ED OUARD DE ROUGEMONT. 

